Best Way To Make a Position Look Like a Hole in the Ground?

I'm trying to figure out what is the best way to make this. I have a trig that marks a position and i want that place to look like a small hole.. as though i dug it up with this hero..

problem is i'm unsure of how to get it to look like a decent hole.

It needs to be walkable cuz i want units to become hidden when they step on it, making it look like they stepped into it.

the only thing i can think of is using a smudge graphic.. which doesnt look right because it makes smoke fly up..

or using a dummy unit that has a burrow animation and giving it locust and making it walkable and invunerable.

any ideas if there is anything better?

Ever tried a "Human Crater" ubersplat with a small but very deep crater effect?

hm. splats. never concidered that. i'll have to look